Carling, of Farmington, said she and her husband Jeremy have been having trouble conceiving naturally. As a child, she battled rheumatoid arthritis and lupus, and the medication she was prescribed to treat it has led to fertility issues.

"We figured that life doesn't always go as planned, and this was only the beginning of that," Carling said.

Determined to have children anyway, she and her husband decided to pursue adoption — a dream of theirs since they were young, she said.

As they waited for the perfect match to become available, Carling said she wanted to become foster parents, too.

"We had room in our house, we had love to give, and we had the resources to help provide a home for children, even if it was going to be short term," Carling said. "We wanted to make a difference in some way while we waited for our family."

The Carlings eventually came to care for Haven and Indie, who were only 5 and 18 months old at the time.

They fostered the sisters for a year, during which time their biological family was still considering whether they would get the girls back, or hand over custody to the Carlings.

In August, the Carlings finally received word that they would have the opportunity to adopt Haven and Indie.

And, as chance would have it, they received the call about twin newborn girls they would be eligible to adopt on that same day.

"We didn't even really have to talk about it for very long, we just knew it was right. We were going to move forward with everything," she said. "When you have had so many failed adoptions, that's the way you start to think."

They scheduled the adoption dates for the twins on October 19, and the date for the sisters the following day — coinciding with her husband Jeremy's 30th birthday.

In a photo posted to Reddit, Carling and her husband could be seen holding their four daughters — Sunny and Weslie, 9 months; Indie, 1; and Haven, 2 — on the day all the adoptions were finalized.

"Now, we can't even imagine life without the girls," Carling said.

To adjust, Carling said she gave up her job to be a stay-at-home mom for her adopted daughters, until they go off to kindergarten.

"I think it's important for one of us to be home with them," Carling said. "Our focus is on them, and giving them the love and attention they need individually and as a group of sisters."